Plate heater



H. W. KLEIST Feb. 15, 1955 PLATE HEATER 2 Sheets-Sheet l Filed Jan. 22, 1952 Feb. 15, 1955 H, W, KL1E|5T 2,702,334

PLATE HEATER Filed Jan. 22, 1952 2 Sheets-Sheet 2 I?? vena? afn/ways United States Patent O PLATE HEATER Herman W. Kleist, Hollywood, lll., assignor to Dole Refrigeratiug Company, Chicago, Ill., a corporation of Illinois Application January 22, 1952, Serial No. 267,535

Claims. (Cl. 219 34) This invention relates to heating apparatus, such as hot plates and the like.

One purpose is to provide a panel or element which can be installed easily in or on the wall, the ceiling, or even the floor, of a room, or which can be positioned in a passage or duct through which air to be heated may ass. p Another purpose is to provide a wall unit which may be connected readily into a heating system general to a plurality of rooms or spaces.

Another purpose is to provide a panel which includes a heating member and a surrounding eutectic with a low melting point, which vaporizes at a predetermined temperature.

Another purpose is to provide a heating panel or element of the type described, which may be hooked readily and easily into and form part of a house electric system.

Other purposes will appear from time to time in the course or" the specification and claims.

I illustrate my invention more or less diagrammatically in the accompanying drawings wherein:

Figure 1 is a side elevation with parts broken away and parts in section;

Figure 2 is a top view of the structure of Figure 1;

Figure 3 is a section, on a slightly enlarged scale, on the line 3 3 of Figure l;

Figure 4 is a similar section through a panel having an alternative filling;

Figure 5 is a perspective view of an application of my system;

Figure 6 is a section on the line 6 6 of Figure 5 Figure 7 is a partial plan view of a plate having ns secured thereto;

Figure 8 is a section on the line 8 8 of Figure 7;

Figure 9 is an elevation of an individual iin;

Figure 10 is a section, on a slightly enlarged scale, on the line 10 10 of Figure 9;

Figure 11 is a perspective view of another n assembly;

Figure 12 is a section on the line 12 12 of Figure 1l;

Figure 13 is a section through a variant form of plate;

Figure 14 is a section through a still different type of plate, with a different heating means therein; and

Figure 15 is a wiring diagram.

Like parts are indicated by like symbols throughout the specification and drawings.

Referring to the drawings, and, particularly, to Figures l to 6, inclusive, I illustrate a panel including side walls 1 and 2, which are spaced from each other, and are shown as uniformly spaced and parallel. The side walls are sealed together around their edges to form a preferably gas-tight interior. I illustrate, for example, circumferential Walls 3, 4, S and 6, which, if desired, may be formed as part of one of the side walls. For example, the assembly including the members 2 to 6, inclusive, may be stamped, and thereafter welded or otherwise secured to a at wall 1, with a circumferential edge of the flat wall 1 abutting and secured to the outwardly extending lianges 7.

Within the panels I illustrate a bent tube 8, the ends of which extend outwardly through the edge wall element 4. It will be understood that the apertures 8a and 8b, through which its ends extend, are suitably sealed. 9 indicates any suitable resistance element located within the tube 8 and advantageously surrounded by any suitable electrical insulating. coating or jacket 10.

I nd it advantageous to iill the space within the thus formed panel, and exterior to the tubing 8, with a heatconductive substance. I nd it advantageous to use a eutectic having a predetermined vaporizing temperature', and which fuses or melts at low temperatures. This eutectic is shown in its solid form as at 15 in Figures 1 and 3. A suitable example of such a eutectic is a fusible alloy, for example, alloys used in re extinguishers and signal alarms, such as Woods fusible metal alloy, having a low melting point, for example, of about 160 F. Woods alloy contains 7 to 8 parts of bismuth, 4 parts of lead, 2 parts of tin, and 1 to 2 parts of cadmium. Another suitable metallic eutectic is that known by the trade name Cerrosafe or Safalloy, which fuses at about 160 F. A further suitable eutectic which fuses at about F. contains 10% cadmium, 50% bismuth, 13.3% tin, and 26.7% lead.

Non-metallic materials may also be used, such as paran wax, acetaldehyde, creosol, cyclo hexane, phenylcyclo-hexane, silico iodoform, and undecyl alcohol.

In Figure 4, I illustrate a view which represents the tube 8 surrounded by a liquid. This may indicate, with equal accuracy, the eutectic 15 when it is above its melting point, or a heat-conductive liquid, oil or the like surrounding the tube 8 and within the interior of the panel.

25 illustrates any suitable valve unit through which air may be exhausted from the interior of the unit. I iind it advantageous to withdraw some air from the space A, to the end that when the eutectic is in liquid form, or when a liquid heat conductor is used, the excess pressure of the atmosphere will hold the side walls 1 and 2 snugly about or against whatever inner structure is employed.

It will be understood that whereas I have illustrated the side walls 1 and 2 as abutting the tube or coil S, any suitable spacing means may be employed about or in addition to the tube, both to maintain adequate heat transfer and also to form or maintain a suitable uniform and p lare surface for the panel, when a plane surface is desire Figures 5 and 6 illustrate a typical application of my heating system to a dwelling space, in which plate units may be employed kin lieu of or as part of baseboards. When so employed, I may use, if desired, any suitable top and bottom moldings 30 andl 31. It will be understood, however, that my plates can be applied in a multitude of ways, and the form of Figures 5 and 6 is illustrated merely as a practical example.

It will be understood, also, that I may advantageously employ finned plates, and these plates may be exposed either directly to the space to be heated or they may be exposed to or form sides or parts of ducts through which air to be heated is drawn or blown. Since a variety of ducts or housings may be employed, no specific duct is shown herein.

I illustrate a suitable flanged plate structure, for example, in Figures 7 to 12, inclusive. In the form of these figures I show a typical plate which may, for example, be formed as shown in Figures 1 to 4, inclusive. Secured to one face of it are aV plurality of vanes 32. It will be understood, of course, that the vanes 32, or their equivalent, may be applied and secured to one surface of the plate by any suitable means. However, l find it advantageous, under some circumstances, to bolt or weld, or otherwise secure, individual n members in such fashion that only the ends of the ns are secured. With reference to Figures 7 to 10, inclusive, the individual tins 32 are each provided with base iianges 33 which abut the opposed surfaces of the wall 2 or" the plate. Each iin is curved or bent at one end, and is provided with end flanges 34 which may be bolted, welded or otherwise secured to that part of the plate in which the walls 1 and 2 are sealed together. By imparting a reverse curvature to the ilange 33 I provide that when the ends or iianges 34 are secured to the plate structure the ange 33 is forcibly opposed to the outer surface of the plate wall 2. The curvature is shown in the detached ilange structure in Figure 9, and the iinal relationship is illustrated in Figure 8.

With reference to Figures 1l and l2, I may, if I wish, secure the iin elements 32a to unitary end pieces 34a, which may be welded, bolted or otherwise secured to the plate structure. Each tin 32a has a base flange 33a.

It will be understood that the battery of ns may also be bent, as shown in Figure 9.

In Figure 13, I illustrate a plate C, one wall of which, 40, is formed with a plurality of oifsets 41 which, in effect, perform the function of vanes, or which substantially increase the exposed heated area, and also substantially increase the inner area exposed to the eutectic.

Whereas I find tubular resistance elements to be practical, and they are shown in the form of Figures 1 to 4, inclusive, and also in the form of Figures 8 and 13, it will be understood that I do not Wish to be limited to any specific type of resistance, or even to the use of resistance elements as heating means. In Figure 14, l illustrate a variant form of plate D, which includes walls 45 and 46, sealed about their edges, as at 47, and defining, between them, a space which is substantially lled by a blanket or pad type of element, shown at 48, and including suitable resistance elements or wires 49 which provide heat in response to the passage therethrough of electric current supplied through any suitable circuit, not herein shown in detail. It will be understood that when a thin pad of heat resistant material or fibre is used, as shown at 48 in Figure 14, it may advantageously be used to space the actual resistance elements or Wires 49, the wires, if desired, being surrounded by any suitable outer layer of electric insulation. In a thin plate, such as is shown in Figure 14, the resistance wires or elements closely approach the inner surfaces of the walls 45 and 46 of the plate in adequate heat exchange relationship. It is important, however, to maintain a close approach of the walls 45, 46 to the resistance element, and I may do so as follows. 50 is any suitable valve through which air may be withdrawn in order to maintain a less-thanatmospheric pressure within the plate D, whereby the sides 45 and 46 are forced together against or about the resistance heating pad 48 by the excess of atmospheric pressure over internal pressure.

It isI thought unnecessary to illustrate specific circuits in any great detail. It will be understood, however, that my plates, however formed, may be connected in any suitable way in any suitable electric or house power circuit. In Figure 15, I illustrate a typical diagram in which a plurality of plates 60, 61, 62 and 63 are connected by suitable conductors 64, to a suitable power supply circuit, including conductors 65 and 66. If desired, the plates may be arranged in series or in parallel, or in any combination of series and parallel arrangement. In Figure 15, for example, I illustrate pairs of plates in parallel, the current for each pair being controlled by an individual temperature-responsive thermostat 67, the pairs themselves being connected in parallel. It will be understood that I may employ unitary control for an entire group of plates or temperature-responsive control for individual plates. However, in heating rooms where more than one plate is located in a room, an advantageous arrangement may be, as shown in Figure 15, an arrangement where groups of plates, arranged in indi* vidual rooms or parts of rooms, are cut in or out by a particular heat-responsive element.

It will be understood that whereas I have described and shown a practical and operative device, nevertheless, many changes may be made in the size, shape, number, proportion and disposition of the parts without departing from the spirit of my invention. I wish my description and drawings to be taken as, in a broad sense, illustrative or diagrammatic rather than as limiting me to my specific showing herein. For example, it will be understood that whereas, for convenience, I illustrate the tube or coil 8 as of circular cross-section, I may employ any suitable cross-section, rectangular or otherwise. It will be realized, for example, that whereas I have illustrated resistance means for heating the various types or" plates shown herein, any other suitable heating means may be employed.

The use and operation of my invention are as follows:

My panel preferably comprises a .housing of bendable sheet metal, the space in the housing being, preferably, under partial vacuum. The heating member, which may be the resistance 9, is preferably so proportioned, in its heating effect, to the volume of the eutectic of Figure 3, to liquefy or melt the eutectic at the predetermined vaporizing, or liquefying, or fusing temperature of the eutectic. As shown at 15a in Figure 4, I may use a heat-conductive liquid. An advantageous way of usmg my unit is to employ it as a wall panel. However, it may be used in any suitable way, and may, for example, be employed in heating a current or currents of air for delivery to a space or room to be heated. Since the means for controlling the passage of air to be heated do not, of themselves, form part of the present invention, they are not herein illustrated. Any suitable ducts or directive housings may be used. My unit lends itself to being mounted in or as part of the Walls or ceiling of a room. For one example, the plane surface of the plate or side wall 1 may be arranged flush with any suitable wall structure, which may be recessed to receive the circumferential walls 3, 4, 5 and 6, and the rear wall 2. In that event, the wiring and the exposed ends of the ducts or tubes 8 are sealed in the wall structure. It will be understood, also, that the outwardly extending ends of the tube 8, as shown in Figures 1 and 2, may be liush, or substantially flush, with the end wall 4, if desired. It will be understood, of course, that in heating a given room or space I may employ one or more long panels or a larger number of shorter panels. The panels may abut, or may be spaced apart. While my system may be used in connection with indirect heating systems, I lind it advantageous to employ my panels as radiant elements, each panel preferably having a wall surface exposed to the space to be heated. Thus, when the enclosed eutectic or fluid is raised to a suitable temperature, the forward face of the plate, as at 1 or 2, may radiate heat directly into the room or space to be heated.

While I describe and show my units as heated by an electric resistance, it will be understood that other means may be employed. I find it advantageous, however, to employ a series or plurality of panels, each having therewithin a properly protected or insulated resistance, the resistances being connected in any suitable circuit.

I claim:

1. In a stand-by heating plate, liexible, generally parallel metal side walls sealed around their edges to enclose a gas-tight space, a body of heat storage material substantially filling the interior of the plate, a heating assembly positioned in said space and located between said walls, said heating assembly being surrounded by the heat storage material, and means for maintaining a lessthan-atmospheric pressure in the space within said plate and for thereby causing outside atmospheric pressure to urge said plate side walls together, said heating assembly including spacing means for limiting the approach of said walls toward each other, the heating assembly having a wall element in heat exchange contact with at least one of the side Walls.

2. The structure of claim l characterized in that the eutectic is normally solid at ambient room temperatures.

3. The structure of claim 1 characterized in that the eutectic is metallic and is normally solid at ambient room temperatures.

4. The structure of claim 1 characterized in that the heating assembly is normally in contact with each of two generally parallel side walls.

5. The structure of claim 1 characterized in that the heating assembly includes a resistance and means for including it in a conductive system in circuit with a source .v of electric current.

References Cited in the tile of this patent UNITED STATES PATENTS 436,864 Abshagen Sept. 23, 1890 573,629 Tyler Dec. 22, 1896 1,379,721 Rapelye May 31, 1921 1,943,062 Driscoll Jan. 9, 1934 2,048,104 Clinefelter July 21, 1936 2,111,251 Spilsbury Mar. 15, 1938 2,237,151 Knez Apr. l, 1941 2,289,204 Milton July 7, 1942 2,460,625 Ellis Feb. 1, 1949 2,547,402 Lucas Apr. 3, 1951 2,554,926 Schoenwald May 29, 1951 FOREIGN PATENTS ,691,305 France Oct. 20, 1930 

